This invention relates to an apparatus for attachment to hand-held bows to provide improved sighting accuracy for the archer. It is useful both with simple bows and with compound bows, employing cables and pulleys.
Accuracy associated with the bow has customarily emphasized sighting systems for distance parameters. Typical sighting systems may employ cross-hairs, sight pins, scopes, laser sights, and the like. Many solutions for such sighting problems employing a great variety of degrees of sophistication, are available from a number of suppliers.
Accuracy is also recognized as being a function of bow handle torque, or twist, in the hand of the bowman. It is well recognized that whenever the bow handle is twisted, accuracy is poor. For example, when the archers hand twists the bow handle to the right, the sight direction to the target shifts to the right of the arrow flight direction, causing the arrow to miss to the left of the target. Similarly, a twist to the left will cause the arrow to miss to the right of the target. Whenever sights, such as pins, cross-hairs, scopes, or lasers, are attached to the bow handle, poor accuracy due to torque, or twist, is generally enhanced.
Corrective apparatus for the bow handle twist problem is commercially available. One approach is a handle design that reduces the tendency of the archer to twist the handle.
Another approach involves the attachment of a bar to the bow handle, the bar providing front and rear sections such as front and rear rifle sights or front and rear cross-hairs. Sighting is done by eye in the same manner used when shooting rifles or handguns. Such sights are difficult to use and accuracy problems persist. The use of systems involving cables and pulleys with compound bows is described in, for example, U.S. Pat. No. 3,486,495 and in U.S. Pat. No. 4,054,118.
There remains an extensive and serious problem in the sighting accuracy of archery bows, brought about by a relatively slight degree of torque, or twist, applied to the bow handle by the archer.